GURPS Prime Directive cover
GURPS Prime Directive is a Powered by GURPS set in the Star Fleet Universe, a variant of the canonal Star Trek Universe.

GURPS Prime Directive, Revised (Fourth Edition)

As a Powered by GURPS product these books can be used without the GURPS Basic set and are a complete game unto themselves.

Vol 1: Creating a Character

Vol 2: Playing the Game

Both Volumes, Bundled together

Print versions coming out early 2020, available direct from Amarillo Design Bureau

The Star Fleet UniverseEdit

The Star Fleet Universe is a mixture of TOS, TAS and fan sources up to 1979 creating a timeline more filled with war then the then canonal timeline.

The Star Fleet Universe used the then canonal Star Trek Spaceflight Chronology and Y(year) counting from the first contact of Humans and Vulcans to follow the tradition of making exactly where in the future Star Trek was set fuzzy. However, that book put the five year mission of Enterprise as taking place 2207-2212 (Y155 to Y160) which is no longer canon (it now being 2265-2270).

The reality is the Star Fleet Universe timeline has many issues making totally it incompatible with the current canonal one but per the canon that existed in 1979 and the fan stuff added later it makes perfect sense.

As a result one can only go by what appeared in the Original Series, the Animated Series, Star Trek Spaceflight Chronology, Franz Joseph Star Trek Star Fleet Technical Manual and supplemental fan information for the canon of this setting. Everything else is off the table.

Notes from the Author on the Revised Edition for 4E Edit

The story didn't change except for proofreading corrections. 

Chapter 1: The empire information was moved to be with the species. There the information for the ISC was expanded. 

Chapter 2: There is more GURPS information on creating a character and it is presented more along the lines of what GURPS players expect in the way of formatting and tables. Point values changed for Cygnans, Andorians, Ethnic Klingon warriors, Hilidarians, Kzintis, Gorns, Orions (the background information changed to be for the species, not what they did as for a job), Andromedan (no point change, but descriptions of the robots were enhanced), Ranel, Phelen, Veltressai (no point change, but background was greatly enhanced with two total paragraphs becoming seven), Q'Naabians (background corrected and enhanced with one paragraph becoming four), Pronhoulites (and background expanded from a paragraph to six), Rovillians (and background expanded from two paragraphs to seven), Korlivilar (and background expanded from one paragraph to three), Seltorian Queens (and background expanded from two paragraphs to four), Seltorian Sages, Seltorian Experts, Jindarians, Vudar, Paravians, and Carnivons. Height and weight table was added. Templates were corrected (Star Fleet Academy, Federation Marine Academy, Federation Marine Boot Camp, and Merchant Marine Academy) or added (Star Fleet Basic Training, Galactic Intelligence Agency Academy, Federation Marshals Service Academy, and "Shake and Bake School") The only one that was untouched was the Merchant Marine Basic Training. 

Chapter 3: Advantages and Disadvantages reflect GURPS move away from classifying them by type. The chapter grew from 31 pages to 65. 

Chapter 4: Skills. This section grew from 14 pages to 38. All skills mentioned in the templates are included. It also includes GURPS information about skills. 

Chapter 5: How to Play. This section includes most of the rules you need to actually play the game. It expanded from 25 pages to 64. The section on Interspecies Medicine was moved to this chapter from Technology. 

Chapter 6: End Game Awards. More GURPS information was added about developing the character. Medals were included with the text about them. Defender of Life was added. 

Chapter 7: Technology. The list "Technology Availability by Empire" was greatly expanded from about half a column to over a column. The non-standard Technical Skill Specializations disappeared with the description of the technology now explaining what skill is needed to operate it. Shipboard equipment expanded from three pages to over seven. Weapons tables now look like GURPS tables and include weapons that adventurers might encounter that are more primitive. 

Chapter 8: The Star Fleet Universe. Let's Play Federation Commander is added. Standard Planetary Classes now include Class T. Circle Trigon is now accurately placed on the Romulan-Gorn-ISC Neutral Zone. Using SFB for Space Combat is expanded to include Federation Commander. A short section titled Commercial Passenger Service was added. 

Chapter 9: Space Combat actually has the GURPS statistics for and rules on fighting. Descriptions and stats for the standard large freighter, Free Trader, security skiff, Federation heavy cruiser, Klingon D7 battlecruiser, Romulan War Eagle, Kzinti command cruiser, Gorn Allosaurus Battlecruiser, Tholian patrol corvette, Orion Pirate light cruiser, and the standard administrative shuttlecraft are included. To help people visualize where things are on the ship, Federation Commander ship cards are used. A section on "Customized Civilian Ships" was added. 

Chapter 10: The sample characters now have the skills they should and the point value has been adjusted accordingly. 

The index now has an additional section that is titled SELECTED TABLES, MAPS, AND CHARTS that should be useful for players and GMs. Since the book is longer, the index is also longer.

Star Fleet Universe Tech LevelsEdit

Both the 3rd and 4th editions of GURPS Prime Directive used the 3e Tech Scale. While on the surface TL11 seems a logical designation one can actually go much lower then that.

TOS' Industrial ScaleEdit

It should be mentioned that, in universe, the Federation had the Industrial Scale.[1][2]

  • B - 1485 - TL4
  • G - 2030 - TL8-9
  • Level 7 - unknown

It is unknown just where the Industrial Scale changed over from letters to numbers.

GURPS TL CalculationsEdit

The Original Star Trek series (TOS) provides a lot of details regarding Federation Technology. The following uses the lowest TL needed to have the advancement.

3e TLsEdit

TOS Transportation: TL9. The transporter is the oddball at TL14.

TOS Weapons & Armor: All over the TL9-11 range. Starships and Stunners are 9, disrupters are 10 and force screens, tractors beams and antimatter missiles are 11.

TOS Power: Antimatter is TL10.

TOS Medicine: Mccoy comments that Federation medicine can deal with every organ of the body but the brain ("Menagerie" and "Spock's Brain"). The Compendium II notes brain transplant as a TL8 (likely late TL8) development. Similarly there is no evidence for and plenty against TL 9's panimmuity in Kirk's time ("Requiem for Methuselah", "For the World is Hollow and I have Touched the Sky", "Journey to Eden"), no evidence of any form of braintaping until the TNG era, and Longevity is another TL9 development missing from Kirk's time ("Deadly Years").

There is one TL9 hiccup in all of this; Mccoy uses something akin to Suspend on Kirk in "Amok Time" which is before "Spock's Brain" and "For the World is Hollow and I have Touched the Sky" (where large amounts of medical knowledge was gained).

So the conclusion from all this is in Kirk's time TOS Medicine is 8 with one 8+1 "Triox compound".

Scotty indicates that the Star Trek timeline deviated from our own because transistors were the technology of choice for spaceships in the 1990s[3] and there is no reference to computer chips.

So TOS is TL(6+3) to TL(7+3) but only if you ignore "Piece of the Action", "Patterns of Force", and Worlds of the Federation.

4e TLEdit

In the GURPS Tech Level scale large hunks of TOS tech wound up as Superscience: FTL travel, transporter, force-field technology, disintegrators (Phasers) and their crude time travel. This removes these from figuring out what the TL is as superscience can be any TL.

The only direct reference to how powerful antimatter is ('less than one ounce (~28.6 grams) of antimatter is more powerful than ten thousand cobalt bombs'[4]) actually does provide some information. A Joule is kg*c^2, so assuming total conversion one gets 5.1408796[5] PJ[6] for "real" antimatter. Tsar Bomba (tested 30 October 1961) produced 240 PJ or nearly 48 times that of the antimatter that 'ripped away half a planet's atmosphere'. Ergo Star Trek antimatter is superscience just as it is for Britannica-5 (though for different reasons) removing it from TL consideration.

"City on the Edge of Forever" and "Piece of the Action" further refute a higher then TL9. Spock must be able to build mnemonic memory circuit able to interface with a tricorder with unfamiliar and inferior TL6 materials[7] and more importantly Iotians who took 100 years to go from TL5 to TL6 even with books on how to build TL6 equipment[8] must be able to take apart one communicator, learn how a part called a transtator works, and be able to reproduce Federation Tech in a "few years".[9] Since TL four levels higher then your own is impossible to study much less reproduce[10] the highest non superscience Federation tech in this case can be is TL9.


The Franz Joseph Star Trek Star Fleet Technical Manual is the lynch pin for the Star Fleet Universe and is the main reference for what equipment in the SFB universe looks like and functions.


Due to contractional agreement the phasers in Prime Directive don't have the functionality of their "true" SFB or TOS counterparts.

The following table uses "off the shelf" items from GURPS Ultra-Tech and Star Trek Star Fleet Technical Manual to form a foundation to tailoring phasers to be more in line with those of TOS. The ∞ means "the weapon has an infinite “cosmic” armor divisor. Only special forms of DR, noted in the weapon type description, apply vs. direct hits."

Type I has an Accuracy of 3 and Rate of Fire of 1. Type II has Accuracy of 6.

Setting Dmg Type-1
Shots GURPS Ultra-Tech
Overload 6dx600 cr ex (T1)
6dx2,000 cr ex (T2)
40 135 NA Mininuke 156
Dmg 7dx5(∞) cor 10 30 Base/3 Holdout Disintegrator 130
Aff (Heart Attack) 20 60 Base * (2/3) Death Beam Setting 122
Heat Dmg 2d(5) burn, sur 2 6 variable Holdout Blaster 123
Stun HT-2 aff 30 90 Base Holdout Nerve Disruptor 122

For simplicity assume ranges (which are actually in meters) are in hexes

Non SuperScience Federation TechEdit

This matches other non superscience tech the Federation had in the TOS era:

  • Hibernation Chamber:[11] TL9
  • Pneumohypo:[12] TL9
  • Diagnostic Bed:[13] TL9
  • Brainscanner:[14] TL9

Non SuperScience Non Federation TechEdit

These are examples of non superscience tech that is not possessed by the TOS/TAS Federation.

  • Androids: TL9[15][16][17]
  • Bioroids and Biofab: TL10[18]; the civilization that built the Shore Leave planet whose last member is now dead.
  • Brain Transplants, normal: TL9[19][20]
  • Brain Transplants, nanosurgery based: TL10[21]
  • Destructive Uploading: TL10[22]
  • Non-Destructive Uploading: TL10[23][24]

The conclusion is the Federation is TL(6+3)^ to TL(7+2)^ due to the transtator (TL6^ per "Piece of the Action")

Wealth in Star TrekEdit

It is clear from various comments that even in Kirk's era the Federation is a Post-scarcity economy. Kirk even states that they can make diamonds, rubies, emeralds, sapphires by the ton and so they are worthless to him and his crew.[25] The only items that seem have any real value are things that take time to build (starships) or cannot be manufactured via the transporter. Dilithium is a particular pain as it is so valuable that the miners of it can, if they were so inclined and Harry Mudd believed, buy planets.[26]

This effectively breaks the TL starting wealth rules.

Star Fleet Universe Divergences From OTLEdit

While much of this has been retconned in the movies and later versions of Star Trek this is how things were regarding canon in 1979 which is the foundation of the Star Fleet Universe.

The ImmortalEdit

In 3834 BCE in the area of Mesopotamia a man was born who quickly discovered he was immortal via "instant tissue regeneration coupled with some perfect form of biological renewal." He would become many famous people including Solomon, Alexander, Lazarus, Methuselah, Merlin, Abramson, Leonardo da Vinci, and Johannes Brahms.

Ancient TimesEdit

Two groups of aliens came to earth. One group who arrived c 2700 BCE became the Olympian gods[27] and the other tried to follow the ideals of Plato while hiding themselve among earth people.[28] Both groups of aliens left Earth after the collapse of the Greek civilization.

Rome Had No Sun WorshipersEdit

Stated by McCoy and accepted as correct by Spock.[29]

In OTL Rome, in fact, had several cults that revered sun gods including Helios Apollo (Sol) from the Greeks, Mithras from the Persians, and Elagabalus from the Syrians. Then from the 3rd century on there was Sol Invictus ("Unconquered Sun") which may have been a new sect or a revival of an old one. So two of these gods in English would have been called "Sun".

18th CenturyEdit

The Preservers visited Earth and relocated some Indian tribes to a distant world.[30]


A being of pure thought and pure energy becomes Jack the Ripper.[31]


In the TOS reality only 6 million died in WWI.[32] In OTL 15 to 19 million died (9 to 11 million military personal with about 6 million civilian casualties) in WWI.


The energy being kills 7 women in Shanghai, China.[33]


In the TOS reality only 11 million died in WWII.[34] In OTL the range is 50 to more then 80 million. (50–56 million directly killed by the war with an additional estimated 19 to 28 million deaths from war-related disease and famine.)

The Prelude to the Eugenic WarsEdit

The creation of supermen via selective breeding who would take over 40 nations in 1993[35] means the program went back at least 2 generations and likely more. At 20 years a generation this puts one in the 1950s at the latest though earlier seems more logical.

The Nazis Were Close to Inventing the Atomic Bomb and Would Use the V2 Rocket to Deliver it.Edit

Spock states this in "City on the Edge of Forever" as a summation of what his tricorder has recorded of the alternate timeline McCoy would create.

In OTL the Nazis didn't even start seriously look at the atom bomb or V2 until they started loosing the war.[36]

In fact Germany only started looking at atom bombs in 1942 putting them three years behind the US program which had started in 1939 and they never caught up--they only got to an early part the 1942 stage of Manhattan project in 1945. From what we can put together the best Germany could have produced in 1946 was a conventionally powered "dirty bomb" : "At best this would have been far less destructive than the atomic bombs dropped on Japan. Rather it is an example of scientists trying to make any sort of weapon they could in order to help stave off defeat." [37]

The V2 has even more problems as in OTL when Hitler was first shown the plans for the V2 in late 1941 he was dismissive of the V2 as essentially an artillery shell with a longer range and much higher cost[38] It was not until 1944 with German moral waning in the face of defeat after defeat that Hitler decided on building the V2.

Also the V2 simply didn't have the ability to carry an A-bomb; the V2 had the ability to carry a 2,200 pounds payload while Little Boy (smallest A-bomb of the time) was 9,700 pounds. This is why Stalin put so many resources into duplicating the Superfortress instead of simply copying the V2 and slapping an A-bomb on top of it.

Nazi Germany was the most efficient state Earth ever knewEdit

This claim by John Gill[39], who is supposed to be a major historian, is total nonsense by OTL.

In OTL per the 1960 book The Rise and Fall of the Third Reich the Nazi hierarchy was a web of competition, with many high officials bitterly opposed to each other. Consequently, their jurisdictions often overlapped and/or collided. Hence, this conflict actually reduced or even, in some cases, completely negated governmental efficiency.

The Integrated Circuit May Have Not Existed Clear Into the 1990sEdit

Scotty comments about 1990s spaceships using bulky and solid transistor units[40] implying the integrated circuit (successfully demonstrated in 1958) didn't exist in TOS timeline as late as the 1990s.


The Outer Space Treaty of 1967 is not signed allowing the United States to launch an orbital nuclear warhead platform to counter a similar launch by other powers in 1968. In OTL only the USSR launched such platforms as part of the “Fractional Orbital Bombardment System” or FOBS.[41]


The United States efforts to counter FOBS is interfered with by Gary Seven to scare it and the USSR out of the arms race. Thanks to interaction with the Enterprise the US version of FOBS explodes exactly one hundred and four miles above the Earth.[42]

Moral issues of the Prime DirectiveEdit

In the TOS era the Prime Directive was not as rigidly followed as it would be in the TNG era where it was effectively dogma and was too often used to short circuit actual moral choice.[43][44]

Time TravelEdit

It was established that time travel the TOS reality (and all the later non Abrams Timeline successors) works under Plastic time[45] which provides an excellent explanation for any and all continuity issues: they are the product of time travel meddling.

Other Star Trek TimelinesEdit

Star Trek has several different "official" timelines:

  • Canonal: Live action TV series (TOS, TNG, DS9, and Voyager) + movies + "Yesteryear" of TAS. It is not Prime.
  • Kelvin Star Trek (the Abrams movies): the product of the 2005 Viacom split where Paramount got the rights to the movies but CBS owned the TV series and toys based on Canonal Star Trek. To allow Paramount to make more Star Trek a special license requiring significant deviation (thought to be around 25% different) from Canonal Star Trek was created and leased to Paramount.[46]
  • Hybrid: For complicated reasons Star Trek Discovery was done under the Paramount license which is why despite being said to be part of canonal Star Trek it looks like it belongs to the Kelvin timeline. The so called Prime timeline is also part of this.

One odd man out in all this is Star Trek Enterprise which thanks to the Temporal Cold War ignores many elements seen in TOS and TNG. Where exactly it fit (or even if it can fit) is unknown.

There is hope that the remerger of CBS and Paramount will fix things but what Star Trek will look like post merger is unknown.

However, this doesn't fix "The Squire of Gothos" which it is stated that Trelane has viewed Earth events 900 years past but Trelane knows about Alexander Hamilton's 1804 duel and forces Uhura to play a piece a Richard Strauss composition from 1880 putting Star Trek around the 2780s.


If found it is likely realities very similar to this will get the "Roddenberry" name.

Related MaterialEdit


  1. Spock's Brain
  2. Wink Of An Eye
  3. "Space Seed"
  4. "Obsession"
  5. 0.0286*2*(299792458)^2
  6. petajoule; 10^15 Joules
  7. At TL9 this is base -5 with an additional -2 minimum for unfamiliar materials, and whatever penalties using inferior materials incurs. So -7 to begin with and possibly higher. At TL11 it simply would not happen as the penalty total is too high. This assumes Spock doesn't have related Wildcard Skills.
  8. The culture was pulled from a King James sized book called Chicago Mobs of the Twenties which may have added tot he details needed to recreated 1920s technology. The Iotians are imitative not inventive.
  9. "A communicator, built using transtator physics, was discovered by the Iotian inhabitants. They quickly abandoned their mobster and jumped at the opportunity presented by the new treasure. The next vessel to orbit Iotie found what at first appeared to be a Federation starbase, complete with uniformed personal and communication Starfleet frequencies" - Worlds of the Federation pg 108
  10. Basic Set 168
  11. "Space Seed"
  12. throughout the TOS era
  13. throughout the TOS era
  14. throughout the TOS era
  15. "What are Little Girls Made of?"
  16. "I, Mudd"
  17. "Return to Tomorrow"
  18. "Shore Leave", "Once Upon A Planet"
  19. "I, Mudd"
  20. "Spock's Brain"
  21. "Spock's Brain"
  22. The Klingon Mind Scanner/Ripper in "Errand of Mercy"
  23. "What are Little Girls Made Of?"
  24. The Klingon Mind Scanner/Ripper in "Errand of Mercy"
  25. "Catspaw"
  26. "Mudd's Women"
  27. "Who Mourns for Adonais?"
  28. "Plato's Stepchildren"
  29. "Bread and Circuses"
  30. "The Paradise Syndrome"
  31. "A Wolf in the Fold"
  32. "Bread and Circuses"
  33. "A Wolf in the Fold". This could have happen in OTL and forgotten given the chaos surrounding the January 28 Incident
  34. "Bread and Circuses"
  35. "Space Seed"
  36. NOVA: Nazis and the Bomb.
  37. NOVA: Nazis and the Bomb.
  38. Irons, Roy. Hitler's terror weapons: The price of vengeance. p. 181.
  39. "Patterns of Force"
  40. "Space Seed"
  41. "Assignment: Earth"
  42. "Assignment: Earth"
  43. Examination of Star Trek's Prime Directive
  44. The Prime Directive: Star Trek's Doctrine of Moral Laziness
  45. "City on the Edge of Forever"
  46. Star Trek Discovery and the Return of Picard: The Controversies Behind The Scenes and Star Trek Discovery: The Prime Deception – CBS and Paramount Viacom Rights Explained
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